Work holding fixture



' Aug. 17, 1948. L, DE Y 2,447,236

WORK HOLDING FIXTURE Filed June 12, 1945 5 Sheets-Sheet 1 I veutor By2mm min E/amzg Aug. 17, 1948. I 1 E 2,447,236

wonx nowme FIXTURE Filed June 12, 1945 :5 Sheets-Sheet 2 x ////l/////////1 v //l I: /////7 Inventor /w ije of circular milling fixture;

Patented Aug. 17 1948 U NI TED STATES PATENT O FFICE Y WORK'HOLDINGFIXTURE Aldege L. Dory, FineMeadow, Conn.

Application June 12, 1945, Serial No. 5995077 4 Claims. (01. 90-60) Thisinvention relates to improvements in work holding fixtures and moreparticularly to the type of fixture used in connection withmilling-operations. Such devices are commonly employed on millingmachines to hold Work pieces to be milled though they may be employedfor other operations such as grinding.

The object of the invention is rigidly to support one or more workpieces in position for a machine operation and to prevent itsdisplacement as a result of the forces applied thereto.

Another object is a gang fixture in which a plurality of pieces may beheld and firmly clamped during a machine operation.

Among its features, my invention embodies a plurality of jaw memberssupported by a fixed jaw, each of which is provided with a, pair ofangular faces at one end, and a movable jaw adapted to be advancedtoward the fixed jaw and the jaw members to clamp work pieces betweenthe angular faces of adjacent jaw members and the fixed jaw whereby athree pointsupportis provided for each work piece.

Other features embody-relieving the jaw memhens in such a mannerthat'the work pieces are engaged by a slightly yielding pressureso' asto compensate for slight irregularities occurring in the sides of thework pieces which are engaged by the faces of the jaw members-and themovable Jaw.

Still other features embody the use of resilient jaw members orresilient clamping members which cooperate with the jaw members so as-toproduce a cushioned holding effect on the work.

In the drawings:

Figure 1 is a top plan View of a milling fixture designed for straightline work and embodying my invention; v

Figure 2 is a transverse sectional view taken on the line2-2 ofFigure'l; g

Figure 3 is a perspective view-ore. jaw member possessing the cushioningcharacteristics;

Figure 4 is a top plan view of a fixture adapted for use on a rotarymilling machine andembodying my invention;

Figure 5 is a transverse sectional view taken on the line 5-5 of Figure4;

Figure, 6 is a detail perspective-view of aresil- .ient'jaw memberwhichmaybe used in conjunction with the fixture illustrated in Figure 4;

Figure '7 is a view similar toFigure 6 ofa'modified form of clamp jawfor use in conjunction with the type of fixture illustrated in Figure-4;

Figure 8 is a top plan view of a'modifiediorm Figure 9 is a transversesectional View taken on theline 99 of Figure 8; and

Figure 10 is a perspective view of a modified form of jaw for use inconnection with the fixture illustrated in Figure 8.

Referring to the drawings in detail, a milling fixture for use instraight line milling is designated generally l5 and comprises a fixedjaw it which is constituted of a U-shaped frame having at opposite endslegs 11. The ends oft-hese legs are drilled and tapped to receiveretaining bolts M3 by means of which a movable jaw i9 is supported'inoperative relation to the fixed jaw 15. Extending transversely throughthe legs I! of the fixed jaw are aligned openings for the reception of aretaining bar 2!, the purpose of which will be more fully hereinafterdescribed. Extending through the bight portion [6 of the stationary jawat spaced intervals are openings 22 "for the reception of bolts 23, theinner ends of which enter screw threaded openings 24' in the rod 21previously referred to.

Mounted'between the arms I! of the U-shaped frame of thefixed jaw l5 arejaw members designated generally 25'. Each such jaw' member comprises abody 26 opening through the upper edge of which is .a slot 21 andopening through the lower edge of which is another slot 28. The rearwall of the slot 21 is formed with a recess 29 against the wall of whichthe rod 2| previously described is adapted to rest, When the jaw members25 are in position within the'fixed jaw I5 the rod 21 is thrust throughthe opening 20 and the slots 29 and the screws 23 are tightened tosecurely hold the rear or inner ends of the jaw members against thebight portion l6 of the fixed jaw 15 as illustrated in Figures 1 and 2.As shownin Figure 1, the forward. ends of the jaw members 25 projectbeyond the ends of the arms l1 ofthe jaw member [5, and these forwardends are 'formed with inclined face .3!) which areadapted'to cooperatewith the movable jaw-I 9 in clamping the-work pieces W inposition in the'fixture. Each jaw member is relieved along one'side as at 3| from apoint intermediate their ends so as to allow a slight resilience tocompensate for irregularity in the work pieces W.

The slots 21 and 28 cooperate to allow the jaw members25 to yield alongits longitudinal axis so that the'work pieces W are clamped firmly. inposition under a slightyielding pressure longitudinally of the jawmembers.

3 having an upstanding flange 34 and an annular groove 35 at thejunction of the body 33 with the flange 34. In this form of fixture thejaw members designated generally 36 are arranged radially so that thework pieces are held in a closed annular row.

Each jaw member 36 comprises a body 38 carrying at its lower rear end atongue 39 which is adapted to seat in the annular groove 35 in order tolock the jaw member in place. A ring shaped cover plate 45 is attachedto the upstanding flange 34 by suitable attaching means, such as screws4| and overlies the upper faces of the jaw members 38 in order to holdthem against accidental displacement. The end of each jaw memberopposite the end carrying the tongue 39 is provided with a pair ofinclined faces 42 which cooperate with the movable jaws to be more fullyhereinafter described in clamping the work pieces W in the fixture. Likethe previously described jaw members, each of the jaw members 36 isrelieved along one side as at 43 to allow slight sideways motion inorder to accommodate slight irregularities in the work pieces. Aspreviously described, the body 33 is substantially ring-shaped in formand extending upwardly in concentric spaced relation with the flange 34is a wall 44 which is provided with radial slots 45 in which movable jawmembers 46 are adapted to slide. The slots 45 are so arranged that theyalign axiallywith the apices of the V-shaped grooves formed betweenadjacent jaw members 36, as will be clearly seen upon reference toFigure 4. As illustrated in Figure 5, each jaw member 46 is provided inits upper edge with a notch 41 for the reception of a compression coilspring 48, one end of which bears against the rear end of the recess 41,while the opposite end bears against a pin 49 carried by a cover plate58, which is held in position on the annular wall 44 by means offastening devices such as screws As shown, the rear or innermost ends ofthe movable jaw members 45 are inclined as at 52 for engagement with afrusto conical block 53, which is mounted to move axially through thering-shaped body 33. Closing the lower open end of the passage throughthe ring-shaped block 33 is a cover plate 54 having an internal screwthreaded opening formed axially therein for the reception of a screwthreaded shaft 55, the inner end of which is swivelly connected as at 56to the frusto-conical member 53, while the outer end carries a suitablecross bar (not shown) by means of which the shaft 55 may be rotatedwithin the opening in the plate 54 so as to advance or retract thefrusto-conica1 block 53 axially through the body 33. It will thus beseen that as the block 53 advances the movable jaw members 46 will beprojected toward the stationary jaw member 35 through the contact of theinclined walls 52 of the jaw members 46 with the surface of the conicalmember 53. In this way the work piece W will be clamped between theouter ends of the movable jaw members 46 and the inclined faces 42 ofthe stationary jaw members 36.

In Figures 6 and '7, I have disclosed certain modifications which may beincorporated in the device just described. The stationary jaw membersfor instance, as illustrated in Figure 6 and designated generally 51,may be formed with slots 58 and 59 in order to provide a certain amountof longitudinal resilience in the jaw members 5'! which, it is to beunderstood, may be substituted for the jaw members 36. The functions ofthe slots 58 and 59 is essentially the same as that of the slots 21 and28 of Figure 3.

Alternately instead of providing the stationary jaw members with suchslots, I may find it desirable to employ a jaw member such as thatdesignated generally 60 with slots BI and 62 in order to provide thedesired resilience when its work clamping end 63 is moved positivelyoutward into work engaging position. When such a movable jaw member isused, it is obvious that the conventional jaw member 36 will be employedin the fixture illustrated in Figures 4 and 5.

In Figures 8 and 9 I have disclosed a further modification of myinvention corresponding in many respects to the structure illustrated inFigures 4 and 5, but provided with a different form of movable jawadvancing means. In this type of device a body 64 of substantiallycircular form is provided at its peripheral edge with an upstandingflange 65 and at the junction of the flange 65 with the body 64 isformed with an annular groove 66. Formed concentrically with the bodybut spaced inwardly from the flange 65 is an annular channel 61 adjacentthe outer peripheral edge of which is a similar channel or groove 68 ofsomewhat lesser depth and about one-half of the width of the channel 61.Extending inwardly from the side wall-of the body 64 and communicatingwith the channels 61 and 68 is a bore 68, the purpose of which will bemore fully hereinafter described.

Attached as by screws 18 to the body 64 concentric with the ring 65 is adisk H which is of a thickness substantially equal to the heighth of thewall or flange 65, which disk is provided with a plurality of radialgrooves 12 in which movable jaws 13 are slidably mounted. Each of thesejaws is provided with a depending lug '14 for a purpose to be more fullyhereinafter described. Like the jaws 25 and 51, the jaws 13 may also beprovided with vertical slots 15 and 16 so, if desired, a jaw 11 (Figure10) having a depending lug l8 and in which the slots 15 and 16 areomitted may be substituted.

Mounted for rotation in the groove 61 is a ring 19 carrying on itsunderside a series of gear teeth which ride in the groove or channel 68previously mentioned. Extending into the bore 69 is a shaft 8| carryingat its inner end a pinion 82, which is adapted to mesh with the teeth 80so that when the shaft is rotated, the ring 19 will revolve in thegroove. A suitable cross bar 83 is fixed in the outer end of the shaftfor the purpose'of facilitating manual operation of the shaft. Formed inthe upper surface of the ring 19 is a spiral groove 84 into whichtherdepending lugs '14 of the movable jaw members 13 are received.Inasmuch as the groove 84 is of spiral formation it will be obvious thatas the ring 19 revolves in its groove under the influence of the pinion82 and shaft 8|, the movable jaw members 73 will be advanced orretracted according to the direction of the motion of the ring.

Seated against the flange 65 are stationary jaw members 85, each ofwhich is provided with a depending lug 86 for entrance into thegro0ve'66 and the inner ends of these jaw members 85 are provided withinclined faces 81 which cooperate with the movable jaw members 13 inclamping a work piece in the fixture. It is obvious that the solid jawmembers illustrated in Figure 10 may be substituted for the resilientjaw members 13 in which event I may find it desirable to employ the jawmmbers'51 illustrated in Figure 6 in place of the jaw members 85 againstthe flange 65. It is also obvious that jaw members of the typeillustrated in Figure 6 may be used in conjunction with the jaw members73, without in any way departing from the spirit and scope of thisinvention.

In operation, it is obvious that work pieces W introduced into thespaces between the movable jaw members or member, as the case may be,and the stationary jaw members of any one of the forms of the inventionherein shown will be clamped firmly against dislodgment when the movablejaw member is advanced. toward the stationary jaw members and each workpiece will be suspended at three points. By reason of the release of thestationary jaw members, their free ends may move slightly from one sideto the other in order to accommodate work pieces W having slightirregularities and that by the use of the resilient jaws or jaw membersthe work will be yieldingly yet firmly held in place when the movablejaw members are advanced into clamping position.

While in the foregoing there has been shown and described the preferredembodiment of this invention it is to be understood that minor changesin the details of construction, combination, and arrangement of partsmay be resorted to without departing from the spirit and scope of theinvention as claimed.

I claim:

1. A work holdin fixture comprising a fixed jaw, a plurality ofindividual jaw members carried by the fixed jaw, a movable jaw, each jawmember comprising a substantially S-shaped body and having oppositelyinclined work engaging faces at one end each of which cooperates withthe movable jaw and a work engaging face of an adjacent jaw member inyieldingly clamping a work piece and means to advance the movable jawtoward the fixed jaw.

2. A work holding device comprising a fixed jaw, a plurality ofindividual jaw members carried by the fixed jaw, a movable jaw, each jawmember comprising a substantially S-shaped 6 body havin oppositelyinclined work engaging faces at one end each of which cooperates withthe movable jaw and a work engaging face of an adjacent jaw member inclamping a work piece.

3. A work holding fixture comprising a fixed jaw, a movable jaw, aplurality of individual jaw members carried by the fixed jaw, eachindividual jaw member comprising an S-shaped body with 'its longitudinalaxis disposed toward the movable jaw, the end of each individual jawmember facing the movable jaw being provided with at least two inclinedwork engaging faces whereby when the movable jaw is advanced toward thefixed jaw work introduced into the fixture will be yieldingly clampedbetween the inclined faces of two adjacent jaw members and the movablejaw.

l. A work holding fixture comprising a fixed jaw, a movable jaw, aplurality of individual resilient S-shaped jaw members carried by thefixed jaw, each such jaw member having inclined work engaging faces eachof which cooperates with the movable jaw and work engaging face of thenext adjacent jaw member in yieldingly clamping a work piece.

ALDEGE L. DERY.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,256,217 Fieldhouse Feb. 12,1918 1,397,409 Duwelius Nov. 15, 1921 2,339,800 Oben-cy Jan. 25, 19442,346,053 Smith Apr. 4, 1944 FOREIGN PATENTS Number Country Date 25,666Great Britain A. D. 1398 29,226 Great Britain Dec. 10, 1914 533,646Germany Sept. 18, 1931

